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Earth Resources Observation and Science (EROS) |
National Elevation Dataset (NED)
Contents: | NED subset image (Grand Canyon) |
back to Elevation Product List Product DescriptionThe National Elevation Dataset (NED) is a seamless raster product derived primarily from USGS 30-meter Digital Elevation Models (DEMs), along with higher resolution data where available. NED data for the conterminous United States, Hawaii, Puerto Rico, the Pacific Islands, and the Samoan Islands is expressed in geographic coordinates (latitude/longitude). It is horizontally referenced to the North American Datum of 1983 (NAD83) and vertically referenced to the North American Vertical Datum of 1988 (NAVD88). The resolution is one arc-second (approximately 30 meters). NED data is also available at 1/3 arc-second resolution (approximately 10 meters) for some areas of the conterminous United States. NED data for Alaska is expressed in geographic coordinates (latitude/longitude). It is horizontally referenced to the North American Datum of 1927 (NAD27) and vertically referenced to the North American Vertical Datum of 1929 (NAVD29). The resolution is two arc-seconds (approximately 60 meters). The following products are available:
The product consists of seamless raster data which is provided according to a user-specified area of coverage. Instantaneous download is available for areas up to 30 square degrees latitude/longitude (in 100 mb files). The data is available in four formats: The 30m Pre-Defined Areas consists of NED data for the conterminous United States, Alaska, Hawaii, Puerto Rico, the Pacific Islands,and the Samoan Islands. The majority of the conterminous US files are provided in blocks of 2 degrees latitude by 6 degrees longitude. Alaska files are provided in blocks of 1 degree latitude by 1 degree longitude. Files for Hawaii, Puerto Rico, the Pacific Islands and the Samoan Islands are provided in blocks of variable geographic areas. The full dataset consists of 110 pre-defined CDs. The NED 30m Pre-Defined Areas are updated every 2 months with the best available elevation data. NED 30m Pre-Defined Areas are available in two formats: Additional Information: NED Homepage Back to TopPrices
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